Impulse generator



Ma 22, 1945. A RE 2,376,781

IMPULSE GENERATOR Original Filed July 19, 1940 Fly. 2;

INVENTOR lee 14. 16:29am.

WITNESSES:

- ATTORNE Patented May 22, 1945 Westinghouse'Electric & Manufacturingrflom puny- East Pittsburgh, Pa acorporation of Pennsylvania original application' July 19'; 1940} Serial No;

346,246! Divided and thisfapplication July Zl),

19.43; Serialt No; 495,410

, roams. (Cl. 1.7 12'52) My 'inventionxrelates to? a: Vapoi' electri'c" device andxpa-rticul'arly to a control system ior applying make-alive'impulsesi t'oithe make-alive electrodesof vapor electric-valves:

This is a division'- of my.- application filed i J my 19; 1940',--Seriai .No; 346,246, and assigned to theassignee of this. invention; which has matured into U S. Patent NO; 2,340,059, OIT'J'QLIIHaTTQB'; 1944v In'the operationLof vapor'electric'converters of the make-alive type, it has heretofore been -cus-- ternary to: utilize auxiliary thermionic" valves or mechanical switchingdevices to apply the neces sary periodic impulses-for initiating the conduct The heretofore ing intervals in the: valves. known? impulsing systems have-had thedisaclvantages in that the thermionic control valves were of shortlife and required' periodic replace ment tose'cure satisfa'ctor-y'operation of the eonve'rter and the -mechanical switchingdevices fre-- quently burned out the contacts or otl ierw'ise became disarranged:

In the control system according tomy inven# tion the periodic impulsesare supplied by meansof an impulse generator ofthe dynamo-e1ectric type having aspecial winding arrangement for producing impulse currents having high narrow positive impulses or so-ca1led*"peaked' wave inn-'- pulses and a relatively 'low" long time negative impulse orso-called flatwave form: This distort'ed waveform is secured byproviding'an-ex-'- citing: or field element having a very narrow ex'--- citing pole and a wide return pole'surfacez The winding for producing the impulse'is'a1so of' a special form having one side of a-ll' oi' the wind I in'gs concentrated' in a singl'e winding slot and the opposite sides-of the'windin'gs distriloutedin a" plurality of slots to producethe desired wave form as described. The impulse generator is-'- driven at =synchronousspeed by any suitable motor pref erably of the synchronoustype.

It is accordingly an object 'of'myR invention to produc an impulse generator providing a dis-"- torted wave form;

It'is afurther object o-fmy invention to provide a control system in which the distorted waveform" rent and voltage wavesRpro'duced by my inip'roveclf control system. I

In the exemplary embodiinent of my invention; an"- alternating current circuit I and. direct curs v rent circuit Zare connectedfiby means' of a suit able transformer 3; the':f1ow of current: through: the transformer 3 being controlled' bytlie: makealive type valves 4, each oi 'the'va'li/esni including a :vap orizalike"cathotlefiti of suitable -material such as==mercury=; a cooperating'anode fiwand ia makeralive electrode- 15 I I The impulse generatorfaccording toimy 'inven tion comprisesa -fi'eldzmember having aiconcen' trate'clfi field: windingz lnlrassociatedi with" a: rela tively- 'narrow facedfpole elementi H". and. a .rela- I tiv'elylar'ge-vfaced pole? return I21 The armature i 31 of the: impuls generator? carries: a pluralityfi on star: connected? sections-1 Mi preferably: an least as great in number as the mahe alivevelectro de 'l to be" operated. Ea'ch' impulse i generating secti'on: I 4" comprises a winding 1 distributed over a sector of the armature surface" and? comprises a plurality 'of winding turns; one :side of all of tlie turns of" the windings-- b'eingt concentrated pref erablyin a singlezarma-ture slot lBmrat least so" grouped that all turns: are substantially simul taneously" subject to the flux fromi the narrow polefa'ce H and the opposite si'des oi these turns being distributedthroughout a plurality'off: slots; Preferablyapproximately half of the return turns are locatedina single slotwhileithe re? maining turns are'distributed' evenlYthroughout a plurality of slots. The phase terminals? of." the windings I 4 are connected to the? several makealive electrodesq 1' preferably through? suitable unidirectional conductors l 1 while the 'star. point 18 of the--windings I4 are connected. to the oath odes: 5 -of the. valves: 4a Preferably a. returner shunt connection I9 is provided for the inverse impulse wave. A suitableunidirectional conduct tor zll isprovided in the shuntconnection. 19. l

A suitable driving, motor 21 is provided. for rotating the impulse generator invsynchronism with the impulses applied to'the anodes 6 ofithe' make a'live type valves 4'; Preferablyg'a" motor of the synchronous type is utilized which may be connectedtb'any suitab'le'in phasesource such as the alternating current circuit I.

In the operation of the control system accord- .ing to my invention, the impulse generator is rotated at synchronous speed so that the concentrated pole ll successively energizes the various armature windings l4. Thus when the concentrated flux from the pole l l cuts the one side of the windings, a sharp voltage impulse 25 is generated. This impulse 25 produces a current impulse 26 also of rapidly rising characteristic and at the end of the impulse period it is desirable to reduce the impulse 2B rapidly to a very low value. This is accomplished as the exciting pole l I passes approximately half of the return turns of the impulse winding l4, thus producing a rapidly decreasing negative peak 21 of potential, and as the impedance of the circuit is considerable the current 24 is rapidly reduced to zero. As the exciting pole l l passes the successive distributed return turns, a relatively low inverse potential 28 is produced which produces a relatively low inverse current 29 extending over a considerable interval of time. The unidirectional conductor I! in series with the make-alive electrode 1 permits the peak potential of the posi tive impulse 25 to be applied to the make-alive electrode 8 and blocks the inverse potential 21 which flows through the return circuit 19 and its associated unidirectional conductor 20.

While for purposes of illustration I have shown and described a specific embodiment of my invention, it will be apparent that changes and modifications can be made therein without departing from the true spirit of my invention or the scope of the appended claims.

I claim as my invention:

1. An impulse generator comprising a field member having one pole face of a few electrical degrees extent and a second pole face of 360 minus a few electrical degrees extent, an armature comprising a plurality of star connected sections, each section having a plurality of winding slots and a winding composed of a plurality of winding turns, one side of each of said turns being positioned in one of said slots and the opposite sides of said turns being distributed throughout a plurality of said slots.

2. An impulse generator comprising a field member including a pair of pole faces shaped to affect a substantially greater flux density at one of said pole faces than at the other, and an armature member, one of said members being rotatable and the other being stationary, said armature including a winding having a plurality of turns with the front sides of said turns being grouped to cut the flux lines at said one pole face substantially simultaneously and the opposite sides being distributed to cut the flux lines at said one pole face other than simultaneously.

3. An impulse generator comprising a field member including a pair of pole faces covering 360 electrical degrees with one pole face extending over but a few degrees and the other extending over the remainder of the 360 degrees to ef fect a substantially greater flux density at said one pole face than at said other pole face, and an armature member, one of said members being rotatable and the other being stationary, said armature including a winding having a plurality of turns with the front sides of said turns being grouped to cut the flux lines at said one pole face substantially simultaneously and the opposite sides being distributed to cut the flux lines at said one pole face other than simultaneously.

4. An impulse generator comprising a field member including a pair of pole faces covering 360 electrical degrees with one pole face extending over substantially less than 180 degrees and the other pole face extending over substantially more than 180 degrees to effect a substantially greater flux density at said one pole face than at the other, and an armature having a plurality of winding slots and a winding comprising a plurality of winding turns with one side of each of said turns being positioned in one of said slots and the opposite sides of said turns being distributed among a plurality of said slots.

5. An impulse generator comprising a field member including a pair of pole faces covering 360 electrical degrees with one pole face extending over substantially less than 180 degrees and the other pole face extending over substantially more than 180 degrees to effect a substantially greater flux density at said one pole face than at the other, and an armature having a plurality of winding slots and a winding comprising a plurality of winding turns, one side of each of said turns being positioned in one of said slots and the opposite sides of approximately one-half of said turns being positioned in another of said slots with the opposite sides of the other half of said turns being distributed among a plurality of the remaining slots.

6. An impulse generator comprising a field member including a pair of pole faces covering 360 electrical degrees with one pole face extending over but a few degrees and the other extending over the remainder of the 360 degrees to effect a substantially greater flux density at said one pole face than at the other pole face, and an armature member, one of said members being rotatable and the other being stationary, said armature having a plurality of winding slots and a winding comprising a plurality of winding turns with one side of each of said turns being positioned in one of said slots and the opposite sides of approximately one-half of said turns being positioned in a second slot following said one slot in the order of movement of said slots relative to a point on said field member with the opposite sides of the other half of said turns being distributed in equal numbers among a plurality of the remaining slots.

7. An impulse generator comprising a field member including a pair of pole faces covering 360 electrical degrees with one pole face extending over but a few degrees and the other extending over the remainder of the 360 degrees to effect a substantially greater flux density at said one pole face than at the other pole face, and an armature comprising a plurality of star connected sections, each section having a plurality of winding slots and a winding comprising a plurality of winding turns with one side of each of said turns being positioned in one of said slots and the opposite sides of approximately onehalf of said turns being positioned in another of said slots with the opposite sides of the other half of said turns being distributed among a plurality of the remaining slots in the section.

LEE A. KILGORE. 

